Preparation and scintillating properties of Sol-Gel Eu(3+), TB(3+) co-doped Lu(2)O(3) nanopowders

• Published in: International journal of molecular sciences 2011, Vol.12 (9), p.6240
• Main Authors: de Jesús Morales Ramírez, Angel, Murillo, Antonieta García, de Jesús Carrillo Romo, Felipe, Hernández, Margarita García, Palmerin, Joel Moreno, Guerrero, Rosario Ruiz
• Format: Article
• Language: English
• Subjects: Crystallization; Europium - chemistry; Gels - chemistry; Luminescence; Lutetium - chemistry; Microscopy, Electron, Transmission; Nanostructures - chemistry; Nanostructures - ultrastructure; Nanotechnology - methods; Oxides - chemistry; Particle Size; Phase Transition; Polymethyl Methacrylate - chemistry; Spectrophotometry, Infrared; Terbium - chemistry; Thermogravimetry; Transition Temperature; X-Ray Diffraction
• ISSN: 1422-0067
• DOI: 10.3390/ijms12096240

Nanocrystalline Eu(3+), Tb(3+) co-doped Lu(2)O(3) powders with a maximum size of 25.5 nm were prepared by the sol-gel process, using lutetium, europium and terbium nitrates as precursors, and ethanol as a solvent. Differential thermal analysis (DTA) and infrared spectroscopy (IR) were used to study the chemical changes during the xerogel annealing. After the sol evaporation at 100 °C, the formed gel was annealed from 300 to 900 °C for 30 min under a rich O(2) atmosphere, and the yielded product was analyzed by X-ray diffraction (XRD) to characterize the microstructural behavior and confirm the crystalline structure. The results showed that Lu(2)O(3) nanopowders start to crystallize at 400 °C and that the crystallite size increases along with the annealing temperature. A transmission electron microscopy (TEM) study of samples annealed at 700 and 900 °C was carried out in order to analyze the microstructure, as well as the size, of crystallites. Finally, in regard to scintillating properties, Eu(3+) dopant (5 mol%), Tb(3+) codoped Lu(2)O(3) exhibited a typical red emission at 611 nm (D(°)→(7)F(2)), furthermore, the effect of Tb(3+) molar content (0.01, 0.015 and 0.02% mol) on the Eu(3+) radioluminiscence was analyzed and it was found that the higher emission intensity corresponds to the lower Tb(3+) content.